A Comprehensive Study of High-Level Free-Carrier Injection in Bipolar Junction Transistors

Citation data:

Japanese Journal of Applied Physics, ISSN: 0021-4922, Vol: 35, Issue: Part 1, No. 7, Page: 3845-3851

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Citations 1
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Repository URL:
http://stars.library.ucf.edu/facultybib1990/1811; http://stars.library.ucf.edu/facultybib/3310
Y. Yue; J. J. Liou; A. Ortiz-Conde; F. Garcia Sanchez
Japan Society of Applied Physics
semiconductor device modeling; bipolar junction transistors; high-level; injection; TIME MODEL; REGIONS; Physics; Applied
article description
This paper presents a comprehensive study on the effects of high-level free-carrier injection on the current transport of bipolar junction transistors (BJTs). Detailed information for the free-carrier concentration, electric field, and drift and diffusion current components in the quasi-neutral base (QNB) under high-level injection are calculated using the modified ambipolar transport equation and using several different approximations for the majority-carrier current in the QNB. It is shown that high-level injection can create a large retarding field which is in the opposite direction of the built-in field associated with the nonuniform doping concentration. High-level injection also enhances recombination in the QNB, thus resulting in a position-dependent minority-carrier current in the region even if the base is thin. Our results further suggest that the widely used zero majority current approximation gives rise to a larger error compared to other lesser known approximations.